DIRECTIONAL DRILLING WITH DOWNHOLE MOTOR ON COILED TUBING

摘要

A downhole adjustable orienting sub is included in a directional drilling tool stringthat is run into the borehole on coiled tubing. The bent housing of the tool string definesa bend angle and a bend point, and the bend point is oriented about the center of the boreby operating the orienting sub. The level of the reactive torque applied to the bent housingas the bit drills on bottom is controlled by selecting the amount of the weight of the coiledtubing that is applied to the bit. The orienting sub can be indexed downhole to providedifferent orientations of the bend point by temporarily reducing and then increasing themud flow rate.